BERKELEY, CA — The team of Berkeley
Lab scientists that announced two years ago the observation
of what appeared to be Element 118 -- heaviest undiscovered
transuranic element at the time -- has retracted its original
paper after several confirmation experiments failed to
reproduce the results.

A technical committee of experts from the Laboratory’s
physics, supercomputing, and nuclear science divisions
is reviewing the data and methodology from that 1999 result.
Subsequent re-analyses of the original data with different
software codes have been unsuccessful in observing atomic
decay patterns, or chains, which would confirm the existence
of element 118.

In a brief statement submitted to Physical Review
Letters, the same publication in which the original
results were announced, the research team stated: "In
1999, we reported the synthesis of element 118 in the
(lead-krypton) reaction based upon the observation of
three decay chains, each consisting of an implanted heavy
atom and six sequential high-energy alpha decays, correlated
in time and position. Prompted by the absence of similar
decay chains in subsequent experiments, we (along with
independent experts) re-analyzed the primary data files
from our 1999 experiments. Based on these re-analyses,
we conclude that the three reported chains are not in
the 1999 data. We retract our published claim for the
synthesis of element 118."

"Science is self-correcting," Berkeley Lab
Director Charles Shank said. "If you get the facts
wrong, your experiment is not reproducible. In this case,
not only did subsequent experiments fail to reproduce
the data, but also a much more thorough analysis of the
1999 data failed to confirm the events. There are many
lessons here, and the lab will extract all the value it
can from this event."

The original experiment and two confirmation runs were
performed at the Laboratory’s 88-inch cyclotron, utilizing
a newly installed device called the Berkeley Gas-Filled
Separator (BGS). In the experiment, targets of lead were
bombarded with an intense beam of high-energy krypton
ions. The detected sequence of decay events for elements
118 and 116, if observed, would be consistent with theories
that have suggested an "island of stability"
for nuclei.

In addition to the confirmation tests at Berkeley, scientists
at the GSI laboratory in Germany and the RIKEN lab in
Japan were unable to duplicate the original reported results.

Shank said that, in retracting the paper, the experimenters
are taking responsibility to clear the record. "The
path forward is to learn from the mistakes and to strengthen
the resolve to find the answers that nature still hides
from us," he added.